1. Field of the Invention
This invention pertains generally to a system and method for handling lazy-portrait printed documents (printing across the continuous paper web to produce paired portrait orientated pages or in “lazy-portrait narrow-end to narrow-end” formatting (LPEE)) so as to generate acceptably oriented pages that are then processed and grouped into pre-designated document sets with continuously numbered pages. More particularly, to a system and method that flips over one half of the LPEE formatted printed paired pages, which permits a desired reorientation of that half of the LPEE formatted printed paired pages to facilitate further processing in a correctly oriented and correctly ordered page-sequence for assembled document sets, wherein when LPEE formatted head-to-head or bottom-to-bottom paired pages are printed, one half of the printed pairs must be flipped over for generation of the correctly ordered page-sequent count in each final assembled document set.
2. Description of Related Art
To fully understand the subject invention, it is deemed worthwhile to stress the difference between existing/traditional “two-up portrait” versus the current and novel subject “lazy-portrait” printing styles and the documents produced by each type of printing scheme. Existing high-speed duplex variable data printing is carried out most frequently with continuous form printers using what is termed a “two-up portrait” format on a continuous web of paper. Two portrait printed sheets are printed side-by-side (both oriented in the same exact direction. This process, the standard in the industry, produces a continuous output of pages where, for example, the first four sheets (eight pages, front and back on four, eventually separate, sheets) appear as shown in FIG. 1-Prior Art. Currently, an advantage of printing in the prior art format is that it is compatible with more existing printers and more existing post-printing equipment for handling the printed sheets. A critical element of the prior art printing method is that to print either black or color markings on both pages, with the headings in color and the body in black, both the black and color-capable printing heads must span the entire width (long-side to long-side of a page) of both the duplexed sheets, WB and WC, respectively (see FIG. 1-Prior Art). Examples of printers that function in this manner are the IBM InfoPrint 4000 and Oce VarioStream 7000. In a typical prior art printing system a continuous stream of traditionally printed sheets (such as the ones shown in FIG. 1-Prior Art) is printed and then moves into a slitter that separates the single steam into two streams of continuous sheets that then enter a cutter and collator for further processing to generate correctly page-sequenced document sets.
For the sake of clarity in relating the subject invention, the dramatic differences between the subject invention and traditional printing techniques is discussed. For the current subject invention the continuous web is printed in a lazy-portrait narrow-end to narrow-end (LPEE) format (as seen in FIGS. 2 and 3, for four pages and two pages, respectively), which is a means for more efficient and cost effective printing of variable and form data onto paper oriented in a lazy-portrait orientation. The term “lazy-portrait” is defined as a portrait oriented page that is generated by printing the page from one wide edge to the other wide edge (side to side) and not from narrow edge or end to narrow edge or end (top to bottom or visa-versa), as is done in every other currently existing printing system.
The critical issue with the subject invention is that when a pair of head-to-head or bottom-to-bottom pages are printed on a continuous stream of paper, the single stream of paper with the paired images must then be separated/slitted into two separate streams of paper with one stream being flipped over to correctly orient and number-sequence the final pages when cut and stacked into a document set (as seen in FIG. 4 for a pair of LPEE printed sheets). The current subject invention presents a system and method for accomplishing this sheet flipping process by flipping one entire stream of post-slitted sheets.
Again, it is noted that conventional/traditional paper handling systems exist that can transport and process paper printed in the existing and traditional two-up portrait style (not the subject paper LPEE orientation). With traditional systems, future document sets have pages that are already aligned head to head, and existing finishing, cutting, and inserting equipment readily handles the orientation of the two-up portrait printed paper by slitting the two-up portrait web of paper in either first to last (1 to N) or last to first (N to 1) document page-sequencing.
U.S. Pat. No. 6,994,005 (an apparatus for slitting, merging, and cutting a continuous paper web) describes an in-line turn-bar that is positioned after slitting and prior to merging the two streams, but this invention only positionally moves one slit lane of paper to overlap with another slit lane of paper, without turning over the obverse to reverse orientation (or face to back orientation). This patent differs from the subject invention in that, since there is no need, suggestion, or teaching to so, it does not turn over the paper orientation.
U.S. Pat. No. 6,595,465 (a turn-bar assembly for redirecting a continuous paper web) describes turning a single web of paper to reorient the travel direction and, in addition, to optionally flip the paper web from obverse to reverse (face up to face down) image orientation in this reoriented travel direction. This patent differs from the subject invention in that it reorients the paper direction, which is not associated with the manner in which a turn-bar is employed in the subject invention.
U.S. Pat. No. 7,021,184 discloses a system and method for providing sheets to an inserter system using a rotary cutter. The '184 patent demonstrates using a turn-bar after the sheets have been cut from a continuous roll of paper. Unlike the '184 system, the subject invention uses a turn-bar before cutting the sheets in a cutter.
With the subject invention, a significant benefit of utilizing a turn-bar after the paper unwinder and before the cutter is that the work-cell layout can be optimized for space and material handling purposes. Additionally, a benefit of this method, as it applies to LPEE printing, is that the paper sheet reorientation through flipping one of the two streams does not require additional equipment at either the printer or insert.